The company took to Twitter to confirm the service-wide outage, which is its first major issue since December 2013.

It wrote: "Sorry [we're] currently experiencing server issues. We hope to be back up and recovered shortly."

Not what Facebook had in mind

While it's likely the service will be up and running again before too much longer, it's probably not what Facebook envisioned when it announced one of the largest acquisitions in tech history on Wednesday.

As a result of the WhatsApp outage, rival service Telegram Messenger is reporting record registrations and has been unable to cope with the demand.

"This is crazy. We're getting 100 new registrations every second. Trying hard to prevent connection issues in Europe," the company tweeted.